Circuit-continuing device



Patented Nov. 4, 1924.

miran STATES HARRY A.. DOUGLAS, OF BBONBON, MICHIGAN.

CIRCUIT-CONTINUING DEVICE.

Application mea april a, 1921. serial No. 458,557.

To all whom t may concern.'

Be it known that I, HARRY A. DOUGLAS, citizen of the United States, residin at Bronson, in the county 'of Branch and tate of Michigan, haveA invented a certain new and useful Improvement in. Circuit-Continuing Devices, of which the ollowin is a full, clear, concise, and exact description.

My invention .relates to circuit continuingl devices which employ contact carrying shells and contact carriers separably assembled with said shells, the contacts upon the shells and carriers being in circuit continu;

- ing enga ement when the shells and carriers are coup ed. My invention has for its object the provision of an improved construction whereby the cont ct carrying shell and the contact carrier se arably coupled therewith are held in 'substantially rigid relation with their axes preferably coincident. My invention is of particular utility when embraced in a reflecting lamp, as lthereby the incandescent -ilament maybe placed and held in proper focus, the lamp base constituting one form of contact carrier in'the structure ofmy invention. A

In carrying out my invention I employ three engaging parts within the bore of the shell, these parts being desirably all carried permanently by the shell. Two of these parts ar preferably in the form of rigid parallel ribs extending along and integrally formed with the shell andy parallel with its axis, these ribs being preferably ninety degrees apart. The third engaging part. is

preferably in the form of a sprin tongue also formed integrally with the s ell and with its free end opposing the space between the ribs and engageable with the contact carrier at a place between the ends of the ribs and the ends of the contact carrier engaging said ribs. The sprin tongue thus holds the contact carrier and s ell" concentric and, by engaging an intermediate portion of the shell, prevents the' contact carrier from'inclining with respect to the shell. If the shell and carrier are coupled by means of bayonet projections, a bayonet projection engaging seat may be formed in the freeend of the s ring tongue.

I wi explain my invention more fully by reference to the accompanying drawing showing the preferred embodiment thereof and in which Fig.l l is a view in side elevation illustrating a contact carrying shell and an incandescent lamp assembled therewith;

Fig. 2 shows a part of the. shell of Fig.) in section and the lamp in elevation, the shell and lamp being at right angles to the position shown in Fig. 1; Fig. 3 is a sectional view 'on line 3-3 of Fig. 2; and F ig. 4 is a pers ective view of the shell.

Li e parts are indicated by similar characters of reference throughout the different figures. f A

The cylindrical metallic shell 1 is formed with two laterally spacedapart ribs or pro-` jections 2 and 3 that project intothe bore of the shell to an extent which corresponds with the clearance or spacing normally intervening between the shell and contact carrier 4, these ribs being. desirably straight and parallel with the axis of the shell and ninety degrees apart, though the invention is not to be thus limited. The shell is also formed with a spring tongue 5 whose free end is opposite the space between the ribs and one hundred thirty five degrees from either rib. This ton ue is so constrained that when its free en is not in engagement with the contact carrier 4 it will project inwardly beyond the osition of the contact which may thus be eld firmly in engagement with the shell'.

As illustrated, the cylindrical contact carrier 4 is the base of an incandescent lamp 6 whose-filament 7 has one terminal connected with a metallic sheath which surrounds the lamp base and engages the shell 1 audits other terminal connected with the central contact 8 on the lamp base. The drawing illustrates a contact carrier 9 fixed within the shell, there being a forwardly. spring pressed contact 10 upon this carrier that engages the contact 8 upon the lamp base.

Bayonet projections 11 extend laterally from the lamp base and are receivable within oppositely disposed seats 12 and 13 forme in the shell, channels 14 and 15 leading to these seats. The bayonet seat 12 is preferably formed in -the free end of spring tongue`5. In order that the shell may not be weakened owing to the formation of the spring therefrom, the channel 15 has its outer end 16 formed by outwardly bulgin the outer end of the shell at 1 6 instead' o totally removing the metal at this point.

The free end of the spring 5 engages an intermediate portion of the lamp base and is e uidistant from the ribs 2 and 3 so that the amp base or other contact carrier is both centrally positioned within the shell lll) the precise details of construction shown as changes may readily be made without vdeparting from the spirit of my invention, but having thus described my invention I claim as new and desire to secure by Letters Patent the following The combination with a cylindrical shell carrying a contact within its bore and formed at its outer enrl with a bayonet channel; of a cylindrical contact carrier having a.v bayonet projection receivable in said channel and engageahle with a bayonet seat formed in said channel to engage the contacts carried by said shell and carrier; two laterall s aced apart projections carried by the s e and projecting within ,the bore thereof to engage said carrier; and a spring tongue also carried lby the shell and having its free end opposite the space between said projections, this tongue end also projecting into the bore of the shell to engage the carr1er,'said bayonet seat being in the .free end of said tongue which margins said channel.

In witness whereof, I hereunto subscribe my name this 30th .day .of March, A. D.,

HARRY A. DOUGLAS. 

